1. Technical Field
The disclosure relates generally to coding mode selection methods and apparatuses using the same, and, more particularly to coding mode selection methods and apparatuses using the same for selecting a suitable coding mode for motion vector estimation from multiple selectable coding modes.
2. Background
Motion vector estimation is an important technique for motion image compression, which is used to estimate correlation between two pictures. Generally, when performing motion vector estimation to a system that is capable of supporting two or more motion vector modes, such as a one motion vector mode (hereinafter referred to as 1MV mode) and a four motion vectors mode (hereinafter referred to as 4MV mode), in order to select a best coding mode for motion vector estimation, respective motion vector information for each motion vector coding mode is calculated at the same time. Next, a determination is made, based on methodology, as to which coding mode to use for motion vector estimation. For example, one conventional coding mode selection method calculates summation of absolute differential (SADs) of blocks in a current image and a corresponding reference image in each coding mode in advance and then selects a coding mode with the smallest difference value from the calculated SADs and selects motion vector information corresponding thereto as a coding mode for use in a subsequent coding process.
The coding mode selection method, however, requires calculating related information for two or more motion vector modes simultaneously, thus additional time for the coding process is required and computational complexity is increased, increasing costs. Furthermore, additional hardware components are required, also increasing costs.